Does Psilocybin Increase Serotonin?

Psychedelic effects of psilocybin correlate with serotonin 2A receptor occupancy and plasma psilocin levels.

Does psilocybin inhibit serotonin?

Psilocybin is a strong agonist of serotonin 2A receptors, and the authors hypothesize that the effects of psilocybin on these areas of the brain are through the actions of serotonin 2A receptors on GABA neurons, reducing brain activity in these areas.

How does psilocybin affect dopamine?

Psilocybin significantly decreased [¹¹C]raclopride BP in the caudate nucleus and putamen consistent with an increase in dopamine activity.